Complementarities and differences in adoption: an application of hazard models to two technologies in Madagascar

This paper explores the adoption of two agricultural technologies, how their patterns of adoption differ, and the relationship between them. The first technology, the System of Rice Intensification, has been studied previously and high rates of disadoption were observed in some areas. The second technology is off-season cropping, the practice of growing crops (primarily potatoes) in the rice fields during the winter season after the rice harvest. The rates of adoption of off-season cropping were much higher than for SRI and very little disadoption was observed. Through this study we are trying to understand the factors that might explain the differences in adoption and how the adoption of and experience with one technology affects the likelihood of adoption of the other. Our analysis uses hazard models, which have only recently been applied to technology adoption. Findings suggest that both methods increase the likelihood of adopting the other, and off-season crop adopters were less likely to disadopt SRI. Liquidity constraints appear to be more of an obstacle to SRI adoption, suggesting that this might help explain the relative success of off-season cropping.technology adoption, hazard models, Food Security and Poverty, International Development,

LABOR, LIQUIDITY, LEARNING, CONFORMITY AND SMALLHOLDER TECHNOLOGY ADOPTION: THE CASE OF SRI IN MADAGASCAR

Although rice accounts for approximately forty-four percent of land under cultivation and forty-six percent of caloric intake in Madagascar, most farmers cannot produce enough rice to feed their families. Total rice production increased little in the country during the 1990s, and yields were stagnant and well below world average yields. Because of the importance of rice for both family income and nutrition and because of the significant role upland rice cultivation plays in deforestation in Madagascar, intensification of lowland rice production has been a major focus of many development interventions. The System of Rice Intensification (SRI) is a method that has been promoted and closely followed in Madagascar for more than ten years. SRI is remarkable for its dramatic increases in yields achieved without external inputs. While the method is more labor intensive, the doubling or even tripling of yields would appear to make the method extremely profitable. Despite its apparent potential and intensive extension efforts in some areas, adoption rates have generally been low, and the average rate of disadoption (the percentage of households who have tried the method and who no longer practice it) for study area was 40 percent. Using survey data from five communities in Madagascar, a sample selection model and a probit model were used to study three related choices farmers must make concerning the SRI. The first is whether to try the method, and then, conditional on having tried the method a farmer must decide how much of his lowland rice area to put in the SRI. Finally, for all subsequent years, a farmer must decide whether to continue using the method. While many adoption studies have looked at the role of liquidity and labor, few have done so in a dynamic setting. We take advantage of reliable recall data and NGO records on technology use to construct a panel data set, which was used to analyze the effects of learning, labor, liquidity, and social benefits over a five-year period. Learning has been the focus of several recent adoption studies, but this study tries to separate the learning effects from the effects of compliance with authority figures and with social and cultural norms. The results show that planting-season labor and liquidity constraints are extremely important factors in the adoption decisions of Malagasy farmers. Although the method is low-external input, the poorest farmers are not able to take advantage of the technology. This result is very important for development policy-makers in Madagascar who have often seen rice intensification as the most important means by which to alleviate rural poverty in Madagascar.Farm Management,

Better Technology, Better Plots or Better Farmers? Identifying Changes in Productivity and Risk Among Malagasy Rice Farmers

In assessing the productivity gains of a new technology, it is often difficult to determine the extent to which observed output gains are due to the technology itself, rather than to the skill of the farmer or the quality of the plot on which the new technology is tried. This problem of attribution is especially important when technologies are not embodied in purchased inputs such as seed or machinery but result instead from changed farmer cultivation practices. Using data based on observations of farmers in Madagascar who simultaneously practice both a newly introduced and traditional rice production methods, we introduce a method for properly attributing observed productivity and risk changes among new production methods, farmers and plots by controlling for farmer and plot heterogeneity using differential production and yield risk functions. Our results help resolve several outstanding puzzling associated with observed low and incomplete uptake and high rates of disadoption of the new system of rice intensification (SRI) in spite of consistent, sharp yield increases on small farmers' fields without application of additional external inputs.Productivity Analysis,

Missed opportunities and missing markets: Spatio-temporal arbitrage of rice in Madagascar

This paper uses an exceptionally rich data set to test the extent to which markets in Madagascar are integrated across space, time, and form (in converting from paddy to rice) and to explain some of the factors that limit arbitrage and price equalization within a single country. In particular, we use rice price data across four quarters of 2000-2001 along with data on transportation costs and infrastructure availability for nearly 1400 communes in Madagascar to examine the extent of market integration at three different spatial scales sub-regional, regional, and national and determine whether non-integration is due to high transfer costs or lack of competition. The results indicate that markets are fairly well integrated at the sub-regional level and that factors such as high crime, remoteness, and lack of information are among the factors limiting competition. A lack of competition persists at the regional level and high transfer costs impede spatial market integration at the national level. Only six percent of rural communes appear to be intertemporally integrated and there appear to be significant untapped opportunities for interseasonal arbitrage. Income is directly and strongly related to the probability of a commune being in interseasonal competitive equilibrium.Marketing,

U.S. Army Corps of Engineers Freshwater Harmful Algal Bloom Research & Development Initiative

Freshwater Harmful Algal Blooms (HABs) are particularly impactful to the U.S. Army Corps of Engineers (USACE), which manages vast freshwater resources and waterways that provide a variety of services including navigation, flood risk reduction, recreation, fish and wildlife management, as well as potable water supply. The Water Resources Development Act of 2018 (WRDA 2018) authorized the U.S. Army Engineer Research Development Center (USACE-ERDC) to implement a 5-year technology demonstration program to deliver scalable technologies for HAB prevention, detection and management that will reduce HAB frequency and effects to our nation’s freshwater resources across scales (e.g. small waterbodies to river reaches), ecoregions (e.g. subtropical Florida to temperate Ohio and New York), and system types (e.g. reservoirs, riverine, lakes). The USACE-ERDC HAB Research & Development (R&D) portfolio features a range of HAB-combatting methods, models, and technologies that may be used alone or in combination to effectively reduce HAB frequency and impacts to water resource development projects across the nation. An overview of USACE-ERDC sponsored HAB R&D projects will highlight the range of HAB methods, models, and technologies in development, and will provide an opportunity to engage with federal, state, local, and university partners

Ideas with impact : how connectivity shapes diffusion

Despite a growing body of research on idea diffusion, there is a lack of knowledge on why some ideas successfully diffuse and stand out from the crowd while others do not surface or remain unnoticed. We address this question by looking into the characteristics of an idea, specifically its connectivity in a content network. In a content network, ideas connect to other ideas through their content the words that the ideas have in common. We hypothesize that a high connectivity of an idea in a content network is beneficial for idea diffusion because this idea will more likely be conceived as novel yet at the same time also as more useful because it appears as more familiar to the audience. Moreover, we posit that a high social connectivity of the team working on the idea further enhances the effect of high content connectivity on idea diffusion. Our study focuses on academic conference publications and the co-authorship data of a community of computer science researchers from 2006 to 2012. We find confirmation for our hypotheses and discuss the implications of these findings

Utilization of inhaled nitric oxide after surgical repair of truncus arteriosus: A multicenter analysis

BackgroundElevated pulmonary vascular resistance (PVR) is common following repair of truncus arteriosus. Inhaled nitric oxide (iNO) is an effective yet costly therapy that is frequently implemented postoperatively to manage elevated PVR.ObjectivesWe aimed to describe practice patterns of iNO use in a multicenter cohort of patients who underwent repair of truncus arteriosus, a lesion in which recovery is often complicated by elevated PVR. We also sought to identify patient and center factors that were more commonly associated with the use of iNO in the postoperative period.DesignRetrospective cohort study.Setting15 tertiary care pediatric referral centers.PatientsAll infants who underwent definitive repair of truncus arteriosus without aortic arch obstruction between 2009 and 2016.InterventionsDescriptive statistics were used to demonstrate practice patterns of iNO use. Bivariate comparisons of characteristics of patients who did and did not receive iNO were performed, followed by multivariable mixed logistic regression analysis using backward elimination to identify independent predictors of iNO use.Main ResultsWe reviewed 216 patients who met inclusion criteria, of which 102 (46%) received iNO in the postoperative period: 69 (68%) had iNO started in the operating room and 33 (32%) had iNO initiated in the ICU. Median duration of iNO use was 4 days (range: 1‐21 days). In multivariable mixed logistic regression analysis, use of deep hypothermic circulatory arrest (odds ratio: 3.2; 95% confidence interval: 1.2, 8.4) and center (analyzed as a random effect, p = .02) were independently associated with iNO use.ConclusionsIn this contemporary multicenter study, nearly half of patients who underwent repair of truncus arteriosus received iNO postoperatively. Use of iNO was more dependent on individual center practice rather than patient characteristics. The study suggests a need for collaborative quality initiatives to determine optimal criteria for utilization of this important but expensive therapy.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152533/1/chd12849_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152533/2/chd12849.pd

Multicenter Analysis of Early Childhood Outcomes Following Repair of Truncus Arteriosus

Background Literature describing morbidity and mortality following truncus arteriosus repair is predominated by single-center reports. We created and analyzed a multicenter dataset to identify risk factors for late mortality and right ventricle-to-pulmonary artery (RV-PA) conduit reintervention for this patient population. Methods We retrospectively collected data on children who underwent repair of truncus arteriosus without concomitant arch obstruction at 15 centers between 2009 and 2016. Cox regression survival analysis was conducted to determine risk factors for late mortality, defined as death occurring after hospital discharge and greater than 30 days after surgery. Probability of any RV-PA conduit reintervention was analyzed over time using Fine-Gray modelling. Results We reviewed 216 patients, with median follow-up of 2.9 years (range:0.1-8.8). Operative mortaility occurred in 15 patients (7%). Of the 201 survivors, there were 14 (7%) late deaths. DiGeorge syndrome (HR:5.4; 95%CI:1.6-17.8) and need for postoperative tracheostomy (HR:5.9; 95%CI:1.8-19.4) were identified as independent risk factors for late mortality. At least one RV-PA conduit catheterization or surgical reintervention was performed in 109 patients (median time to reintervention:23 months, range:0.3-93). Risk factors for reintervention included use of pulmonary or aortic homografts versus Contegra® bovine jugular vein conduits (HR:1.9; 95%CI:1.2,3.1) and smaller conduit size (HR per mm/m2:1.05; 95%CI:1.03,1.08). Conclusions In a multicenter dataset, DiGeorge syndrome and need for tracheostomy postoperatively were found to be independent risk factors for late mortality after repair of truncus arteriosus, while risk of conduit reintervention was independently influenced by both initial conduit type and size

High-Frequency Oscillatory Ventilation Use and Severe Pediatric ARDS in the Pediatric Hematopoietic Cell Transplant Recipient

INTRODUCTION: The effectiveness of high-frequency oscillatory ventilation (HFOV) in the pediatric hematopoietic cell transplant patient has not been established. We sought to identify current practice patterns of HFOV, investigate parameters during HFOV and their association with mortality, and compare the use of HFOV to conventional mechanical ventilation in severe pediatric ARDS. METHODS: This is a retrospective analysis of a multi-center database of pediatric and young adult allogeneic hematopoietic cell transplant subjects requiring invasive mechanical ventilation for critical illness from 2009 through 2014. Twelve United States pediatric centers contributed data. Continuous variables were compared using a Wilcoxon rank-sum test or a Kruskal-Wallis analysis. For categorical variables, univariate analysis with logistic regression was performed. RESULTS: The database contains 222 patients, of which 85 subjects were managed with HFOV. Of this HFOV cohort, the overall pediatric ICU survival was 23.5% (n = 20). HFOV survivors were transitioned to HFOV at a lower oxygenation index than nonsurvivors (25.6, interquartile range 21.1-36.8, vs 37.2, interquartile range 26.5-52.2, P = .046). Survivors were transitioned to HFOV earlier in the course of mechanical ventilation, (day 0 vs day 2, P = .002). No subject survived who was transitioned to HFOV after 1 week of invasive mechanical ventilation. We compared subjects with severe pediatric ARDS treated only with conventional mechanical ventilation versus early HFOV (within 2 d of invasive mechanical ventilation) versus late HFOV. There was a trend toward difference in survival (conventional mechanical ventilation 24%, early HFOV 30%, and late HFOV 9%, P = .08). CONCLUSIONS: In this large database of pediatric allogeneic hematopoietic cell transplant subjects who had acute respiratory failure requiring invasive mechanical ventilation for critical illness with severe pediatric ARDS, early use of HFOV was associated with improved survival compared to late implementation of HFOV, and the subjects had outcomes similar to those treated only with conventional mechanical ventilation

Patents and Industrialisation. An Historical Overview of the British Case, 1624-1907

A Report to the Strategic Advisory Board on Intellectual Property Policy (SABIP), U